1. Field of the Invention
The present invention relates to a method for manufacturing carbon fibers and method for manufacturing an electron emitting device using the carbon fibers, method for manufacturing a display using the electron emitting device, and an ink for producing a catalyst for use in these methods.
2. Description of the Related Art
A field emission-type (FE-type) electron emitting device, wherein electrons are emitted from a metal surface by applying a strong electric field of 106 V/cm or more toward a metal, has attracted attention as one of cold cathode electron-emitting devices. The practical use of the FE-type cold cathode electron-emitting device may enable realization of an emissive thin display device and contribute reduction of power consumption and weight saving.
FIG. 7 shows the structure of a vertical FE-type electron emitting device. In the Figure, 71 refers to a substrate; 72 to a extraction electrode (gate electrode); 73 to a cathode electrode; 74 to an insulating layer; 75 to an emitter. 76 to a positive electrode (anode) and 77 to a shape of an electron beam irradiated to a positive electrode 76. It has a structure (hereinafter referred to as Spindt type) wherein an opening is formed in a stack of the insulating layer 74 and the extraction electrode 72 arranged on the cathode electrode 73 and a conical emitter 75 is arranged in the opening (for example, see C. A. Spindt, “Physical Properties of thin-film field emission cathodes with molybdenum cones”, J. Appl. Phys., 47, 5248 (1976)).
In addition, as an example of a lateral FE-type electron emitting device, there may be mentioned a device wherein an emitter having an acute tip and a extraction electrode extracting (drawing) out an electron from the emitter tip are formed parallel to a substrate and a collector (called as an anode in the present case) is constituted in the orthogonal direction toward the direction that the extraction electrode and the emitter face each other.
Furthermore, an electron emitting device using fibrous carbon has been proposed (for example, see Japanese Patent Application Laid-Open No. H08-115652, Japanese Patent Application Laid-Open No. 2000-223005, and European Patent Laid-Open No. 1022763).
As a method for manufacturing carbon fibers on the substrate, there is a method for manufacturing the same by disposing catalyst particles comprising a metal on the substrate and thermally decomposing a carbon compound such as a hydrocarbon using the catalyst particles as nuclei. As a method for disposing said catalyst particles onto the substrate, there is known a method of directly forming a catalyst metal by a depositing technology, e.g., a sputtering method. Also, a method of using a metal complex (for example, see Japanese Patent No. 2903290) and a method of using a metal nitrate or a metal chloride have been reported (for example, see Japanese Patent Application Laid-Open No. H03-260119).